Keyboard assembly

ABSTRACT

A keyboard assembly is provided. The keyboard assembly includes a keyboard having at least one input key assembly positioned within the housing and an infection controllable apparatus attached thereto.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is a continuation of application Ser. No. 11/351,568,filed Feb. 10, 2006, which claimed the benefit of U.S. ProvisionalPatent Application No. 60/654,527, filed Feb. 17, 2005; U.S. ProvisionalPatent Application No. 60/691,374, filed Jun. 17, 2005; and U.S.Provisional Patent Application No. 60/748,886, filed Dec. 8, 2005, thedisclosures of which are all hereby expressly incorporated by reference.

TECHNICAL FIELD

The presently claimed subject matter relates generally to data input orsignal generating devices and more specifically to data input or signalgenerating devices such as keyboard assemblies, having a cleanable topsurface.

BACKGROUND

Generally described, a wide variety of keyboards are utilized for signalgenerating functions, generating data entry terminals, and remotecontrol terminals. Typically, each key of each key assembly of thekeyboard corresponds to a particular alphanumeric, such as a specificnumeral, character, letter, or operation. Often the key assemblies arecomplex in construction and operate not only to make switch contact, butto provide an operator with a tactile sensation or feedback. Such keyassemblies employ a wide variety of structures ranging from springloaded switches to dome-type switches to provide this tactile feedbacksignal.

Although the above-described keyboards are effective for data entry,they offer a distinct disadvantage in that they are a source susceptibleto the spreading of infectious agents, resulting in the contamination orinfection of the user. Moreover, the keyboards include numerous creviceswhere grime and infectious agents can reside. Further, these crevices,such as the area between adjacent keys, make the keyboard hard and/orimpractical to clean, since a cleaning cloth or tool may be difficult orimpossible to operate between adjacent keys and any cleaning solventused may pass between adjacent keys and contact the electronics of thekeyboard, thus damaging the keyboard.

Keyboards are frequently used in work areas in the presence ofinfectious germs and other hazardous materials. Keyboards and otherequipment in these environments often must be cleaned at regularintervals to reduce the risk of spreading disease and infection. Thesecleaning intervals can be set to a variety of conditions, including apredetermined period of time or a defined amount of equipment usage.

To facilitate cleaning, membrane keyboards have been developed thatincorporate a substantially smooth top. Although previously developedmembrane keyboards help reduce the spread of infectious diseases byproviding a cleanable top surface, they are not without their problems.For instance, currently available membrane keyboards generally includekey assemblies of a high actuation force and low travel length type.More specifically, actuation force is the force required to transition akey of the key assemblies from a normally raised position to a depressedposition in which a signal is generated. Actuation forces are typicallydivided into two classifications: low actuation forces and highactuation forces. A low actuation force is generally characterized asless than about 0.3 lbf. Conversely, a high actuation force is generallycharacterized to be more than about 0.3 lbf.

The term “travel length” refers to the distance that the key is movedbetween the raised position and the depressed position. Travel lengthsare typically divided into three classifications: low travel; mediumtravel; and full travel. Low travel is for keys which travel less thanabout 0.02 inches between their raised position and their depressedposition. Medium travel is for keys which travel between about 0.02inches to about 0.06 inches between their raised position and theirdepressed position. Full travel is for keys which travel more than about0.06 inches between their raised position and their depressed position.

As previously developed cleanable keyboards do not have a way to alertusers that the keyboard requires cleaning, the burden is on the user tokeep track of the scheduled cleaning intervals. Furthermore, because thepreviously developed cleanable membrane style keyboards having keyassemblies of the high actuation force and low travel length type, theyare not suitable for touch typing (i.e., typing performed on a keyboardhaving key assemblies of a low actuation force and medium-to-full traveltype such that a user can type with relatively no fatigue and withpositive feedback of switch contact), which is preferred in most dataentry terminals. Since previously developed cleanable membrane stylekeyboards are not touch-type keyboards, a user is unable to type forlong periods of time without looking at the keyboard and/or withoutexperiencing fatigue in his or her hands.

SUMMARY

A combination keyboard and cover assembly constructed in accordance withone embodiment of the present invention is provided. Such a keyboard andcover assembly includes a keyboard having at least one input keyassembly positioned within the housing and a cover. The cover is sizedand configured to substantially incase the keyboard and has asubstantially flat top surface to resist wrinkling during use. The coveralso includes a predetermined flexibility to substantially mechanicallyisolate one input key assembly from a second input key assembly during akey stroke input travel distance of at least 0.05 inches.

This summary is provided to introduce a selection of concepts in asimplified form that are further described below in the detaileddescription. This summary is not intended to identify key features oressential features of the claimed subject matter, nor is it intended tobe used to limit the scope of the claimed subject matter.

DRAWINGS

The foregoing aspects and many of the attendant advantages of thepresently claimed subject matter will become better understood byreference to the following detailed description, when taken inconjunction with the accompanying drawings, wherein:

FIG. 1 is a partially exploded perspective view of a keyboard assemblyformed in accordance with one embodiment of the presently claimedsubject matter showing a keyboard cover removed from a keyboard;

FIG. 2 is a top planar view of the keyboard assembly of FIG. 1 showingthe keyboard cover disposed over the keyboard, the keyboard cover beingsufficiently translucent to permit a user to view the keyboard disposedbelow the keyboard cover;

FIG. 3 is a cross-sectional view of the keyboard assembly of FIG. 2, thecross-sectional cut taken substantially through Section 3-3 of FIG. 2;

FIG. 4 is a partial cross-sectional planar view of a portion of thekeyboard assembly of FIG. 3 showing one key assembly of the keyboardassembly in a raised position;

FIG. 5 is a partial cross-sectional view of the key assembly of FIG. 4showing the key assembly in a depressed position;

FIG. 6 is a partial cross-sectional view of a portion of the keyboardassembly of FIG. 3 showing a touch pad of the keyboard assembly;

FIG. 7 is a partially exploded perspective view of a keyboard assemblyformed in accordance with another embodiment of the presently claimedsubject matter showing a keyboard cover removed from a keyboard, thekeyboard having an actuation layer, a switch layer, and a base layer,wherein each layer is shown spaced from the others for clarity;

FIG. 8 is a partial cross-sectional view of a key assembly of thekeyboard assembly of FIG. 7;

FIG. 9 is a perspective view of a top of an alternate embodiment of akeyboard assembly formed in accordance with the presently claimedsubject matter;

FIG. 10 is a perspective view of a bottom of the keyboard assembly ofFIG. 9;

FIG. 11 is a cross-sectional view of the keyboard assembly of FIG. 9,the cross-sectional cut taken substantially through Section 11-11 ofFIG. 9;

FIG. 12 is a partial cross-sectional view of a homing indicia of thekeyboard assembly of FIG. 11;

FIG. 13 is a partial cross-sectional view of a leading edge of thekeyboard assembly of FIG. 11;

FIG. 14 is a partial cross-sectional view of a trailing edge of thekeyboard assembly of FIG. 11;

FIG. 15A is a partial cross-sectional view of a portion of a sensorassembly of the keyboard assembly of FIG. 9;

FIG. 15B is a partial cross-sectional view of a portion of an alternatesensor assembly of the keyboard assembly of FIG. 9;

FIG. 16 is a cross-sectional view of a keyboard position adjustmentassembly of the keyboard assembly of FIG. 10, the cross-sectional cuttaken substantially through Section 16-16 of FIG. 10, the keyboardposition adjustment assembly shown in a retracted position;

FIG. 17 is a view of the keyboard position adjustment assembly of FIG.16, the keyboard position adjustment assembly shown in an extendedposition;

FIG. 18 is a cross-sectional view of a key assembly suitable for usewith the above described embodiments;

FIG. 19 is an perspective view of a light guide assembly suitable foruse with the key assembly of FIG. 18;

FIG. 20 is a block diagram of a user interface system for managing theoperation of the keyboard and exchanging data with the user;

FIG. 21 is a graphical user interface for managing the operation of thekeyboard and exchanging data with the user; and

FIGS. 22A and 22B are functional flow diagrams indicating operation ofthe keyboard assembly of FIG. 9.

DETAILED DESCRIPTION

The presently claimed subject matter is described herein with referenceto the accompanying illustrations where like numerals correspond to likeelements. One suitable embodiment of a keyboard assembly 100,constructed in accordance with the presently claimed subject matter isillustrated in FIGS. 1-6. The keyboard assembly 100 includes a pluralityof input key assemblies 108 disposed within a housing to form a keyboard104. Such a keyboard assembly 100 can be used in combination with anyconventional system, such as a computer, word processor, calculator,data entry terminal, control panel and the like, to generate signalsand/or to enter data into the system.

For clarity in the following description, directional terms such asvertical, horizontal, downwardly, upwardly, etc., have been used todescribe one suitable embodiment of the keyboard assembly 100, whereinthe key assemblies 108 are mounted on a horizontal plane and extend awayfrom the plane in an upward manner. However, it will be appreciated thatthe keyboard assembly 100 may be mounted in any orientation, thus, thedirectional terms will change accordingly. Therefore, such terms shouldbe viewed as merely descriptive and non-limiting.

The keyboard assembly 100 includes a cover 102 removably coupled to thekeyboard 104. The cover 102 has a substantially smooth top surface 106,which is substantially free of crevices so as to be amenable tocleaning. In one embodiment, the cover 102 is substantially free offeatures on the top surface 106 which exceed a selected depth or heightfrom the top surface 106, such as about 0.02 inches, 0.015 inches, 0.010inches, or 0.005 inches. Preferably, these features are subtle andlocalized features either convex or concave in shape so as to havesmooth transitions amenable to cleaning, for example, by wiping with acloth. In another embodiment, the cover 102 is substantially free ofcrevices such that a cloth can pick up foreign material, such as germs,with a simple wiping action.

When assembled, the cover 102 is disposed over, or encases, the keyassemblies 108. To actuate the key assemblies 108 underlying the cover102, a user types upon the cover 102. The key assemblies 108 arepreferably medium-to-full travel key assemblies requiring low actuationforces to permit a user to use the keyboard assembly 100 in a touch-typemanner. The cover 102 may be removed and cleaned, or alternately,cleaned when disposed over or encasing the key assemblies 108, to reducethe spread of infectious diseases.

In light of the above general description of the keyboard assembly 100,the components of the keyboard assembly 100 will now be described ingreater detail. The keyboard 104, as stated above, includes a pluralityof key assemblies 108. The key assemblies 108 are of any suitable designthat is currently known or to be developed in the future, a few suitableexamples being elastomeric tactile style key assemblies, metal domestyle key assemblies, elastomeric dome style key assemblies as shown anddescribed, or spring loaded style key assemblies. For the purposes ofthis detailed description, the term “dome” refers to domes having asemi-spherical shape as well as domes of any other geometric shape.

Referring to FIG. 4, while only one of the key assemblies 108 will bedescribed in detail for the sake of brevity, those skilled in the artwill appreciate that the description of the single key assembly 108pertains equally well to the other key assemblies 108 of the keyboardassembly 100. In that regard, the key assembly 108 of FIG. 4 includes amoveable key 110, a plunger 112, a key support structure 114, anactuation layer 116, and a switch contact 118. The key assembly 108 isdisposed above a switch layer 120 having a switch layer contact 122.

During use, when a user applies a downward force on the moveable key 110equaling or exceeding the actuation force of the key assembly 108, themoveable key 110 moves from its raised position (as shown in FIG. 4)toward the switch layer 120 to a depressed position (as shown in FIG.5). This depressed position results in switch closure. Specifically, theswitch contact 118 of the moveable key 110 electrically contacts theelectrical contact of the switch layer contact 122, as shown in FIG. 5.Such switch closure results in the generation of a signal, andoptionally, an associated data entry.

During movement of the moveable key 110, the key support structure 114supports the moveable key 110 and guides the moveable key 110 along avertical axis of the key assembly 108. After the actuation force isremoved from the moveable key 110, the actuation layer 116 returns themoveable key 110 to the raised position shown in FIG. 4.

Still referring to FIG. 4, each individual element of the key assembly108 will now be described in detail, beginning with the key supportstructure 114. The key support structure 114 is adapted to support andguide the moveable key 110 when the moveable key 110 is pressed andreleased. In the embodiment shown, the key support structure 114 isconstructed in the form of a bezel housing that includes a base plate124 having upwardly extending side walls 126. The side walls 126 extendfrom the base plate 124 to form a hollow key silo 128.

At least partially disposed in the hollow key silo 128 is the plunger112. The plunger 112 includes a vertically disposed bore 130 extendingtherethrough. The bore 130 forms a socket for receiving a shaft of themoveable key 110 to couple the moveable key 110 to the plunger 112, forexample, in an interference fit relationship. While the moveable key 110is described above and illustrated as being a separable part from theplunger 112, it will be readily evident that the moveable key 110 andthe plunger 112 may alternately be integrally formed as a unitarymember.

The plunger 112 is disposed in sliding arrangement within the side walls126 of the key support structure 114. In one embodiment, the plunger 112is preferably keyed to the key support structure 114 so that themoveable key 110 is impeded from rotating relative to the key supportstructure 114. The key support structure 114 may be of a unitaryconstruction, preferably made from a semi-rigid, or rigid material, onesuitable example being a polycarbonate material.

The actuation layer 116 is constructed out of an elastomeric material,such as silicon rubber, and is disposed directly below the key supportstructure 114 and substantially parallel to the base plate 124. Theactuation layer 116 may be of a unitary construction integrally formedwith a depressible dome 132, the dome 132 being associated with themoveable key 110.

In the embodiment shown, the depressible dome 132 is generally circularin cross-section and of a suitable size such that the dome 132 providesa generally uniform upward force and uniform support for its associatedmoveable key 110 across the entire bottom surface of the moveable key110.

The upward force, or biasing force, which the depressible dome 132applies to the moveable key 110 maintains the moveable key 110 in theraised position until a user applies an actuation force which overcomesthe biasing force, resulting in the downward movement of the moveablekey 110 to the depressed position. In the illustrated embodiment, theforce of actuation required to transition the moveable key 110 from theraised position to the depressed position is selected such that the keyassembly 108 is suitable for touch-typing. For instance, in oneembodiment, the key assembly 108 is a low actuation force key assembly108, having an actuation force less than any one of the followingforces: about 0.3 lbf, 0.2 lbf, 0.1 lbf, 0.08 lbf, or 0.06 lbf.Preferably, the actuation force of the key assemblies 108 is betweenabout 0.1 lbf and about 0.2 lbf.

When the moveable key 110 is depressed, the bottom surface of themoveable key 110 presses downwardly, equally and symmetrically, on thedepressible dome 132 so that the dome 132 flexes or deforms downwardlyand uniformly around its entire cross-section as shown in FIG. 5. Thedepressible dome 132 includes an electrically conductive contact 118mounted on the bottom surface of an extension 113 of the dome 132,facing the switch layer 120.

In the embodiment shown, the electrically conductive contact 118 is aunitary member extending the entire width of the bottom of the extension113. Alternatively, the contact 118 can be made up of a plurality ofsmaller dimensioned contacts disposed around the perimeter of the bottomsurface of the extension 113. In operation, the contact 118 contacts anassociated electrical contact 122 on the switch layer 120 when thedepressible dome 132 is sufficiently depressed by the moveable key 110to produce the desired switching effect and associated data entry.

In the illustrated embodiment, the length of travel 134 of the moveablekey 110 from its raised position to its depressed position is selectedsuch that the key assembly 108 is suitable for touch-typing. Forinstance, in one embodiment, the key assembly 108 is a medium travel ora full travel key assembly 108, having a length of travel 134 greaterthan any one of the following: about 0.05 inches, about 0.06 inches,about 0.08 inches, about 0.10 inches, about 0.12 inches, about 0.14inches, about 0.16 inches, about 0.18 inches, about 0.20 inches, orabout 0.22 inches. Preferably, the travel length 134 of the keyassemblies 108 is between about 0.06 inches and about 0.16 inches.

Still referring to FIG. 4, the key assembly 108 further includes theswitch layer 120, a spacer layer 135, and a base layer 136, all of whichare parallel to and disposed directly below the actuation layer 116. Theswitch layer 120 may be a well-known printed circuit board and may becarbon coated to prevent corrosion. In addition, the switch layer may beformed by any conventional method, such as a copper cladding process ora printed silver ink process. The spacer layer 135 suspends the switchlayer 120 above the base 136, the base 136 forming a bottom of a housingof the keyboard 104.

Referring to FIG. 6, the keyboard 104 may also include a well-knowntouchpad 140. The touchpad 140 detects and tracks finger motion abovethe touchpad 140. To move a cursor associated with the user's fingerdisposed above the touchpad 140, the user lightly slides his or herfinger over the portion of the cover 102 disposed above the touchpad 140surface. The touchpad 140 translates the finger's location above thetouchpad 140 into cursor movement.

Referring to FIG. 1, the cover 102 will now be described in greaterdetail. The cover 102 includes a substantially smooth top surface 106which is substantially free of crevices so as to be amenable tocleaning, as mentioned briefly above. Extending perpendicular downwardabout a perimeter of the top surface 106 is a sidewall 142. The sidewall102 is adapted to fit about a shoulder 144 of the keyboard 104,preferably in an interference fit relationship, thereby removablycoupling the cover 102 to the keyboard 104. Although the cover 102 isillustrated and described as being removably coupled to the keyboard104, it should be appreciated by those skilled in the art that the cover102 may also be integrally formed or permanently attached to thekeyboard 104.

The cover 102 is made from a flexible material such that the cover 102may deform when pressure is applied to it to reciprocate the moveablekey between its normally raised position and the depressed position. Thecover 102 is formed from a material that is able to deflect or stretchlike a trampoline during use so that the key assembly 108 disposed belowthe cover 102 can actuate with very little to no extra resistance causedby the cover 102. For instance, the cover 102 may be made from aflexible material that increases the actuation force of a low actuationforce, medium-to-full travel key assembly by less than any one of thefollowing values: about 50%, 40%, 30%, 20%, 10%, or 5%. In a preferredembodiment, the flexible material increases the actuation force of thekey assembly by less than 25%.

The cover 102 is preferably made from a flexible material with apredetermined flexibility to substantially mechanically isolate one keyassembly 108 from the other key assemblies 108 during use. In thatregard, the flexibility of the material permits a user to press thecover 102 in one location to activate a selected key assembly 108without activating any adjacent key assemblies 108.

Although the cover 102 has a predetermined flexibility to substantiallymechanically isolate one key assembly 108 from the other key assemblies108 during use, it should be appreciated that some compression ofadjacent key assemblies 108 may occur when one key assembly 108 issufficiently depressed by an actuation force to be actuated, thusresulting in a desired switching effect and associated data entry.However, such adjacent compression is generally insufficient to actuatethe adjacent key assemblies 108 (i.e., to produce a desired switchingeffect and associated data entry by the adjacent key assemblies 108).

In one embodiment, the material of the cover 102 is of a selectedflexibility permitting low actuation force, medium-to-full travel keyassemblies of a standard keyboard, for example, located on a ¾″ centerto center spacing, to be individually actuated from the raised positionto the depressed position without causing adjacent key assemblies toalso be actuated. In another embodiment, a top layer of the cover 102has a thickness substantially between about 0.01 inches and about 0.2inches. In another embodiment, the top layer has a thicknesssubstantially between about 0.02 inches and about 0.08 inches, with apreferred value of about 0.031 inches.

One suitable material for constructing the cover 102 is an elastomerthat resists wrinkling when coupled to the keyboard, such as a siliconeelastomer. In one embodiment, the cover 102 is made of an elastomerhaving a durometer rating substantially between about 20 and about 40,with a preferred rating of about 30. In another embodiment, the cover102 is formed from a soft urethane material or any other material thatcan be stretched and which is then able to return to its originalconfiguration.

The cover 102 may include one or more protective coatings added to thetop surface 106 to resist contaminants from being absorbed into theelastomer and resist degradation of the elastomer by an adverse chemicalreaction. The cover 102 may also include protective coatings added toimpede the growth of infectious material upon the cover 102, such asantibacterial based coatings. The cover 102 may be formed from atranslucent, transparent, or opaque material, or any combinationthereof, to permit the key assemblies 108 to be visible through thecover with substantial clarity.

The cover 102 may further include indicia 138 disposed on the cover 102to indicate to a user the alphanumeric associated with the keyassemblies 108 disposed below the indicia. The indicia 138 may be visualor physical in nature, such as text printed on the cover 102, an outlineof an outer perimeter of the key assemblies 108 disposed below theindicia, a change in the texture of the cover 102, slight indentation(s)on the cover 102, and/or raised structure(s) on the cover 102.

Such indentations or raised structures may be convex or concave in shapeso as to be free of crevices, and such indentations or raised structuresmay or may not resemble the alphanumerics associated with the keyassemblies 108. It should be appreciated that printed indicia may benegatively illuminated (the indicia is opaque and the surrounding areais transparent or translucent) or positively illuminated (the indicia istransparent or translucent and the surrounding area opaque).

In the illustrated embodiment, one suitable indicia 138 is shown as theletters “ESC” printed, indented, or raised upon the cover 102 anddisposed over the key assembly 108 associated with an escape operationof a computer (not shown) coupled to the keyboard 104. Although only asingle indicia 138 is shown in the illustrated embodiment for purposesof clarity, it should be appreciated by those skilled in the art thatthe cover 102 may include multiple indicia 138, such as one for everykey assembly 108, or a lesser number, such as indicia 138 disposed aboveselected reference keys, such as above the keys associated withcharacters “F” and “J” in a standard English (or QWERTY) keyboard.

In light of the above description of the components of the keyboardassembly 100, the operation of the keyboard assembly 100 will now bedescribed. Referring to FIG. 1, the cover 102 is removably coupled tothe keyboard 104 such that the cover 102 completely covers or encasesthe underlying keyboard 104, including the key assemblies 108. Referringto FIG. 2, a user views the underlying key assemblies 108 through thetranslucent cover 102, and places his or her fingers in a typingposition, aided by indicia 138 disposed on the cover 102. Alternatively,the user locates his or her fingers by printing on the cover 102, theprinting being located in the vicinity of the corresponding keys. A userthen performs touch-type typing.

Referring to FIG. 5, as the user's finger 146 contacts the cover 102disposed above a key assembly 108 and presses downward with a forceequaling or exceeding the actuation force of the key assembly 108 (whichis preferably a low actuation force of about 0.3 lbf or less), themoveable key 110 underlying the cover 102 moves downward an amount equalto a medium-to-full travel length. As the moveable key 110 movesdownward, the switch contact 118 associated with the moveable key 110contacts the contact 122 associated with the switch layer 120, resultingin a desired switching effect and associated data entry.

The cover 102 is of sufficient flexibility such that when one keyassembly 108 is fully actuated, adjacent key assemblies 108 are notinadvertently actuated. Further, the cover 102 is of sufficientflexibility such that the actuation force of the key assembly 108 is notappreciably increased by the force required to deflect the cover 102.Specifically, even with the cover 102 in place over the keyboard 104,the actuation force of the key assembly 108 is still a low actuationforce for allowing a user to perform touch typing without significantfatigue.

Referring to FIGS. 7 and 8, a keyboard assembly 200 constructed inaccordance with another embodiment of the present disclosure isillustrated. The keyboard assembly 200 is substantially similar instructure and operation to the keyboard assembly 100 illustrated anddescribed above in relation to FIGS. 1-6 with the following exceptions.The keyboard assembly 200 is an elastomer style version of the abovedescribed keyboard, and as such, is constructed without the moveable key110, plunger 112, and key support structure 114 illustrated anddescribed with regard to FIG. 4. Inasmuch as the two embodiments aresubstantially similar, for the sake of brevity, the following paragraphsfocus generally on the aspects of the keyboard assembly 200 that deviatefrom the previously described embodiment.

The keyboard assembly 200 includes a cover 202 and a keyboard 204. Thekeyboard generally includes three layers, namely, from top to bottom, anactuation layer 210, a switch layer 206, and a base layer 208. The cover202 and the three layers (210, 206, and 208) making up the keyboard 204are substantially similar in construction and operation to thecomponents of the above described embodiment bearing the same names, andtherefore will not be described in detail.

The cover 202 wraps around the keyboard 204. A top surface 212 of thecover 202 is substantially flat and contains substantially no key-topfeatures. Because the key-top features are substantially or entirelyeliminated, the accumulation of contaminates on the keyboard assembly200 are reduced. As a result, the keyboard assembly 200 can be easilycleaned.

The cover 202 suitably includes indicia 214 (see FIG. 7) indicating thefunction of the key, such as a letter of the alphabet that will beentered when the key is depressed, or a function, such as the letters“ESC” (signifying the “escape” function). The cover 202 may includesupport webs 222 (see FIG. 8) which extend downward from the top surface212 of the cover 202 to engage the actuation layer 200 between adjacentkey assemblies 216 to aid in the support and suspension of the cover 202above the key assemblies 216.

The key assemblies 216 are generally of a low actuation force,medium-to-full travel variety. Each key assembly 216 includes a biasingmember in the form of a depressible dome 218 which normally biases acontact pad 220 in an upward, non-contact, raised position, as shown inFIG. 8.

When the user presses downward on the cover 202 above the contact pad220, the depressible dome 218 exerts an upward resistant force on thekey assembly 216 that is being depressed. Thus, the user must overcomethe upward resistant force to sufficiently depress the key assembly 216to obtain switch closure and associated data entry. After the userreleases his or her downward force on the key assembly 216, the upwardforce exerted by the depressible dome 218 returns the contact pad 220 toits raised position.

A keyboard assembly 300 constructed in accordance with anotherembodiment of the present disclosure may be best understood by referringto FIGS. 9-21. The keyboard assembly 300 is substantially similar inconstruction and operation to the keyboard assembly embodiment describedwith reference to FIGS. 1-8. Therefore, the following paragraphsgenerally focus only on aspects of the keyboard assembly 300 differentfrom the embodiments described above.

The keyboard assembly 300 of FIGS. 9-19 the keyboard assembly 300includes homing indicia 360 for helping a user to properly locate his orher fingers upon the keyboard assembly 300, a wraparound cover 302 forenhanced cleanability and aesthetics, and sensor assemblies 370 and 372for detecting keyboard assembly 300 cleaning. The keyboard assembly 300also includes a keyboard position adjustment assembly 380 (see FIG. 10);and a user interface system 450 (see FIG. 20) for managing the operationof the keyboard assembly 300.

Referring to FIGS. 9 and 12, homing indicia 360 are disposed on thecover 302 to indicate to a user a desirable hand or finger location onthe keyboard assembly 300. The homing indicia 360 may be visual orphysical in nature. As non-limiting examples, homing indicia 360 withinthe scope of the present disclosure includes text or images printed onthe cover 302; an outline of an outer perimeter of the key assemblies308 disposed below the homing indicia 360 on the cover 302; a change inthe texture of the cover 302; slight indentation(s) on the cover 302;and/or raised structure(s) on the cover 302. As best seen in FIG. 12,the homing indicia 360 are in the form of convex bumps which are free ofcrevices and thus easily cleanable.

The homing indicia 360 of the illustrated embodiment may be disposed inone or more predetermined locations upon the cover 302 to aid a user inlocating their hands/fingers in a preselected position upon the cover302. In one embodiment, the homing indicia 360 are located on the cover302 over the key assemblies 308 associated with selected reference keys,such as above the keys associated with characters “F” and “J” in astandard English keyboard and upon the “5” key of the numerical pad, tohelp a user properly locate their hands and fingers upon the keyboardassembly 300 in a standard position.

As discussed briefly above, the cover 302 may be of a wrap-arounddesign. For example, referring to FIG. 11, the cover 302 wraps around atop surface 362 and side wall 364 of the keyboard 304, and couples to abottom surface 366 of the keyboard 304. This “wrap-around” feature ofthe cover 302 may provide an aesthetically pleasing look to the keyboardassembly 300, as the ends of the cover 302 are substantially hidden fromview. As configured, the ends of the cover 302 are located underneaththe keyboard 304.

Further, because the cover 302 substantially covers, and preferablycompletely covers, the top surface 362 and the sides 364 of the keyboard304, the top surface 362 and sides 364 are encased by an easilycleanable and substantially crevice-free material. Such encasementimpedes the accumulation of dirt and infectious substances upon thekeyboard 304, and provides a keyboard assembly 300 having both top 362and side surfaces 364 that are easily cleanable.

Referring to FIGS. 13 and 14, the cover 302 of the illustratedembodiment is suitably coupled to the keyboard 304 by a couplingassembly 390. In the illustrated embodiment, the coupling assembly 390includes a tongue 392 and groove 394 arrangement. More specifically, theends of the cover 302 terminate in lips or tongues 392. The tongues 392are sized and shaped to be cooperatively received within grooves 394disposed slightly inward of an outer perimeter of the bottom surface 366of the keyboard 304.

The cover 302 couples to the bottom surface 366 of the keyboard 304 suchthat the outer surface of the cover 302 and the bottom surface 366 aresubstantially coplanar. Such coplanar configuration provides an easilycleanable surface as it does not include any substantial crevices,abrupt changes in height or contour, or protrusions formed at theinterface between the cover 302 and the bottom surface 366 of thekeyboard 302.

In one embodiment, the tongue 392 is sized and shaped to sealinglyengage the groove 394 to impede fluid ingress at the interface cover 302and bottom surface 366. Although a specific coupling assembly 390 isillustrated and described, it is noted to those skilled in the art thatother coupling assemblies 390 are suitable for use with and are withinthe spirit and scope of the presently claimed subject matter. Asnon-limiting examples, the cover 302 may be retained by many othercoupling assemblies, such as fasteners, a few suitable examples beingsnaps, hook and loop fasteners, adhesives, clamps, etc.

Further, although a specific coupling assembly 390 is illustrated anddescribed for coupling the cover 302 to the keyboard 304, it should benoted that the coupling assembly 390 is optional and may be eliminated.For example, the cover 302 may be sized and configured to be stretchedover the keyboard 304, with the resiliency and elasticity of the cover302 retaining the cover 302 to the keyboard 304 after the stretchingforce is removed. Additionally, although the cover 302 of the presentlyclaimed subject matter is illustrated as only covering a portion of thebottom surface 366 of the keyboard 304, it should be appreciated bythose skilled in the art that the cover 302 may alternately completelyor substantially encompass the keyboard 304.

Referring to FIG. 9, the sensor assemblies 370 and 372 will now bedescribed in greater detail. The sensor assemblies 370 and 372 areadapted to detect or sense user input. As a non-limiting example, a userinput may be a cleaning of the keyboard assembly 300 with a cleaningfluid, such as water or alcohol. Inasmuch as the first and second sensorassemblies 370 and 372 are identical in construction and operation, onlythe first assembly 370 will be described for the sake of brevity.

Referring to FIGS. 9 and 15A, the first sensor assembly 370 is asuitable conductive sensor assembly, including a first electrode orelement 374 a and a second electrode or element 374 b. As the user wipesor applies a cleaning fluid 378 (optionally, with a cloth or towel) tothe cover 302 during cleaning, the fluid 378 forms an electrical bridgebetween the first and second electrodes 374 a and 374 b. As a result,the electrodes 374 a and 374 b become electrically connected with oneanother, and the resistance between electrodes 374 a and 374 b isreduced.

After the cleaning fluid 378 has sufficiently bridged electrodes 374 aand 374 b together (i.e., the resistance between electrodes 374 a and374 b has been reduced to a predetermined amount by the cleaning fluid378), the first sensor assembly 370 sends a signal to a controller 454(FIG. 20) indicating that the first sensor assembly 370 has detected thepresence or application of a cleaning fluid 378 to the keyboard assembly300. The controller 454 includes a well-known sensor controller (notshown) and a keyboard controller (not shown). Likewise, as the cleaningfluid 378 is applied to the keyboard assembly 300, first and secondelectrodes 376 a and 376 b of the second sensor assembly 372 becomeelectrically connected with one another.

After the cleaning fluid 378 has sufficiently bridged electrodes 376 aand 376 b together, the second sensor assembly 372 sends a signal to thesensor controller 454 indicating that the second sensor assembly 372 hasdetected the presence of a cleaning fluid 378. Although two sensorassemblies 370 and 372 are described in the illustrated embodiment, itshould be appreciated that more or less than two sensor assemblies arewithin the scope of the present disclosure.

One sensor controller suitable for use in the present embodiment ismanufactured and sold by Cypress Semiconductor Corporation of 198Champion Ct., San Jose, Calif. 95134 under the model numberCY8C21534-24PVXI. One keyboard controller suitable for use in thepresent embodiment is manufactured and sold by Cypress SemiconductorCorporation of 198 Champion Ct., San Jose, Calif. 95134 under the modelnumber CY8C24794-24LFXI.

The controller 454 is suitably programmed to monitor the duration oftime between receipt of the signals indicating the presence of acleaning fluid from each of the sensor assemblies 370 and 372. If theduration of time is within a certain range of time, then the controller454 will acknowledge an input, e.g., a “successful cleaning” of thekeyboard assembly 300. In another embodiment, the controller 454 may beprogrammed such that all sensor assemblies 370 and 372 must send theirsignals indicating the presence of a cleaning fluid 378 within apredetermined amount of time of each other before an input, e.g., a“successful cleaning” of the keyboard assembly 300, is acknowledged bythe controller 454.

The sensor assemblies 370 and 372 are configured to be in communicationwith a warning assembly 456, as described in greater detail below. Insuch a configuration, after an input (e.g., a “successful cleaning” ofthe keyboard assembly 300) has been acknowledged by the sensorcontroller 454, a predetermined condition used to determine the state ofthe warning assembly 456, such as a predetermined interval, is reset tothe beginning of the interval (such as “zero”).

As a non-limiting example, the predetermined condition or interval maybe a predetermined time period. In such a case, the predetermined timeinterval (monitored by, for example, a timer) is reset to time equal tozero. If this predetermined time interval passes before a new successfulcleaning of the keyboard assembly 300 is acknowledged by the sensorcontroller 454, then the user will be notified by a warning signalissued by a warning assembly 456.

Thus, the warning assembly is at least partially operatively coupled tothe keyboard assembly, and includes at least a first state and a secondstate. The first state of the warning assembly 456 indicates theexpiration of a predetermined interval, such as a time interval. When inthe first state, the warning assembly 456 provides a warning signal.Some non-limiting, but suitable examples of an warning signal include: avisual signal, such as a flashing light associated with the keyboard ora text message appearing on a display screen associated with thekeyboard; an audible signal, such as a beep or voice message; afunctional signal, such as locking of the keyboard such that thekeyboard will not function until a successful cleaning has been logged;and/or a physical signal, such as the vibrating of the keyboard. Thesignal may be selectable changeable by the user. In one embodiment, agraphical user interface is operably connected to the keyboard assembly300 to permit a user to selectively change the signal (see FIG. 21).

The second state of the warning assembly 456 indicates the duration of apredetermined interval, such as a time interval. When in the secondstate, the warning assembly 456 does not provide a warning signal andalso indicates that a predetermined cleaning condition has been met.

Although the illustrated embodiment of the warning assembly 456 isdescribed as indicating the passage of a predetermined time interval(i.e., a predetermined amount of time since a “successful cleaning”), itshould be appreciated that any number of parameters could be used to setthe predetermined cleaning interval. Such parameters include apredetermined number of keystrokes, after the computer is powered off oron a predetermined number of times, login by a new user, or any otherinterval for determining or monitoring usage of the key board. Each ofthe foregoing may also be referred to as “warning trigger sources,” asdescribed below with respect to FIGS. 22A and 22B.

The parameters of the predetermined interval are selectably changeablyby the user. In one embodiment, a graphical user interface is operablyconnected to the keyboard assembly 300 to permit a user to selectivelychange the parameters of the predetermined interval (see FIG. 21).

Referring to FIG. 15B, an alternate embodiment is shown in which asingle capacitance proximity sensor 396 is used in place of each sensorgroup 370. Capacitance proximity sensors 396 are well-known in the artand readily available. Therefore, for the sake of brevity, theirfunction will not be described in detail herein.

In the illustrated embodiment, the capacitance proximity sensor 396 isdisposed under the cover 302 and the top surface 362 of the keyboard304, although it should be readily appreciated that other placements arealso possible. In use, the capacity proximity sensors 396 detect achange in capacitance when an object is placed within its electricfield. Different objects create different changes in capacitance,thereby allowing the capacitance proximity sensors 396 to differentiatebetween.

For example, the capacitance proximity sensor 396 can differentiatebetween the user's hand, the user's hand holding a dry cloth 398, andthe user's hand holding a cloth 398 wetted with cleaning fluid 378. Forthat reason, as a non-limiting example, the capacitance proximity sensor396 may be tuned so that the above conditions are distinguishable fromeach other.

Of note, although the illustrated embodiments are illustrated anddescribed as having either a pair of sensor assemblies (whether of theconductive or capacitance type), it should be appreciated by thoseskilled in the art that any number of sensor assemblies in any number oflocations may be used without departing from the spirit and scope of thepresently claimed subject matter. Multiple sensors help ensure that theentire keyboard assembly is cleaned during cleaning, opposed to just onearea of the keyboard assembly. Further, sensors may be substantiallyvisually isolated within the keyboard assembly. In this regard, thesensors may be located inconspicuously within the keyboard assembly tohelp ensure that the user cleans the entire keyboard assembly ratherthan just around the known locations of the sensors.

It should also be noted that although specific sensor types areillustrated and described for use with the presently claimed subjectmatter, other types of sensors for detecting whether or not a successfulcleaning evolution has occurred are within the present disclosure. As anon-limiting example, another type of sensor is actuation of a “cleaningcomplete” switch on the keyboard by a user after they have cleaned thekeyboard. Another non-limiting example, another type of sensor is anoptical liquid sensor able to detect the presence of a certain chemicalor component of a cleaning fluid.

As may be best understood by referring back to FIG. 9, the keyboardassembly 300 may also include a clean mode system (lock-out assembly) tominimize the risk of inadvertent keyboard activation during cleaning.The clean mode system includes an activation button 600, a status light602, and a warning light 604. The activation button 600 is a standardon/off switch coupled to the keyboard.

When cleaning of the keyboard is desired or required, the operatorpresses the activation button 600. This action will turn on the statuslight 602 to indicate to the operator that the keyboard is in a“CLEAN-MODE.” Pressing the activation button 600 simultaneouslydeactivates the keyboard, such that in the event that keys areinadvertently pressed during cleaning, no data is sent to the host. Thisallows the operator to safely clean the keyboard.

After the keyboard is cleaned, the operator again presses the activationbutton 600. This causes the status light 602 to turn off, therebyindicating that the keyboard is no longer in CLEAN-MODE. The keyboard issimultaneously reactivated so that data can again be sent to the host.

If the keyboard is in CLEAN-MODE and a period of time elapses withoutthe operator pressing the activation button 600, the CLEAN MODE will beautomatically turned-off. As such, the status light 602 is turned-offand the keyboard is reactivated. A typical period of time for thisautomatic reactivation could be about 15-120 seconds, with 30 secondsbeing preferred. The actual period of time can be set by a systemsadministrator and according to use.

Still referring to FIG. 9, operation of the clean mode system will nowbe described in greater detail. In a typical protocol of operation, thewarning light 604 will start to flash to indicated that cleaning isrequired. This functions as a signal to notify an operator that cleaningis required. The operator must then put the keyboard into clean mode bypressing the activation button 600 so that the keyboard can be safelycleaned. This, in turn, causes the status light 602 to be activated.Proper cleaning of the keyboard by a wipe-down protocol will cause thewarning light 604 to go off. The operator will then press the activationbutton 600 a second time to reactivate the keyboard.

Although the use of the warning light 604 is preferred, otherembodiments are within the scope of the present disclosure. As anon-limiting example, the clean mode system can be put into CLEAN-MODEwithout the warning light 604 being activated. Therefore, suchembodiments are within the scope of the present disclosure.

Referring now to FIGS. 10 and 11, the keyboard position adjustmentassembly 380 of the keyboard assembly 300 will now be described ingreater detail. The keyboard position adjustment assembly 380 permits aninclination and/or height of the keyboard assembly 300 relative to asupport surface 384 to be adjusted, thereby allowing a user to select aproper ergonomic position for the keyboard assembly 300 during use.

The keyboard position adjustment assembly 380 includes one or moresupports 382 a, 382 b, 382 c, and 382 d. The supports 382 are adapted torest upon the support surface 384 and support the keyboard at a selectedheight and inclination above the support surface 384. One or more of thesupports 382 may be adjustable in height such that a user mayselectively adjust the height and/or inclination of the keyboard.

Turning to FIGS. 16 and 17, the right rear support 382 b is shown. Theright rear support 382 b includes a cover 386 and a height adjustmentmechanism 388. The cover 386 may be coupled to the bottom surface orenclosure 366 of the keyboard assembly 300 and at least partially housethe adjustment mechanism 388 therein. The cover 386 is preferablycoupled to the bottom enclosure in manner that does not result in theformation of crevices, such that the cover 386 provides an easilycleanable surface. Moreover, the cover 386 is coupled to the bottomenclosure 366 such that the transition between the cover 386 and thebottom enclosure 366 is substantially free of abrupt changes in contour,height, angle, etc., such that the outer surface of the cover 386provides a smooth transition to the outer surface of the bottomenclosure 366.

The adjustment mechanism 388 may be a push button style adjustmentmechanism, such that pressing the adjustment mechanism 388 causes theadjustment mechanism 388 to toggle between two or more positions, suchas a retracted position as shown in FIG. 16 and an extended position asshown in FIG. 17. For instance, pressing on the adjustment mechanism 388causes the adjustment mechanism to toggle from the retracted position tothe extended position. Pressing the adjustment mechanism again causesthe adjustment mechanism 388 to toggle back to the retracted position.

The adjustment mechanisms 388 associated with the rear supports 382 aand 382 b travel between the retracted and extended positionsapproximately between about 0.2 inches and 1 inch, with a preferredtravel distance 383 of about 0.6 inches. However, it should be notedthat other travel distances, either more or less than the distancesrecited herein, are suitable for use with and within the spirit andscope of the presently claimed subject matter.

The pressing force used to actuate the adjustment mechanism 388 betweenthe retracted and extended positions is preferably large enough toprevent inadvertent closing by pressing on the keyboard assembly 300. Alocking mechanism (not shown) may also be used to lock the adjustmentmechanism 388 in a selected position to impede inadvertent actuation orchange in height. Although the adjustment mechanism 388 is illustratedand described as a push button style adjustment mechanism, those skilledin the art will appreciate that the adjustment mechanism may take anysuitable form that permits the support 382B to be adjusted in length,without departing from the spirit and scope of the presently claimedsubject matter.

Any combination of adjustable and non-adjustable supports may be used.For instance, in one embodiment, only the rear supports 382 a and 382 bare adjustable in height. In another embodiment, all four supports 382a, 382 b, 382 c, and 382 d are adjustable in height. In yet anotherembodiment, only the front supports 382 c and 382 d are adjustable inheight. In still yet another embodiment, none of the supports areadjustable in height. Although the illustrated embodiment is illustratedand described as having four supports, it should be noted that anynumber of supports are suitable for use with and are within the spiritand scope of the presently claimed subject matter, including one, two,three, four, or five or more. Also, the supports may be eliminated alltogether.

Referring to FIG. 18, the components forming the keyboard assembly 300will be described in greater detail on a layer by layer basis. The toplayer of the keyboard assembly 300 is the cover 302. As discussed indetail above, the cover 302 may be a flexible, easily cleanable,translucent material, which is substantially free of crevices.

The key assemblies 308 are disposed directly below the cover 302. Thekey assemblies 308 of the illustrated embodiment of FIG. 18 are of awell-known scissor type key assembly arrangement, although anywell-known or to be developed key assembly may be used without departingfrom the spirit and scope of the presently claimed subject matter.

As discussed in detail above, the key assemblies 308 are preferablymedium-to-full travel key assemblies requiring low actuation forces topermit a user to use the keyboard assembly in a touch-type manner. Eachkey assembly 308 may be formed from transparent or translucent materialsor is at least substantially formed from transparent or translucentmaterial to permit a high percentage of light striking the key assemblyto pass therethrough.

A key assembly support layer 400 may be disposed below the keyassemblies 308. The key assembly support layer 400 may be used toprovide a rigid or semi-rigid frame or base for supporting the keyassemblies 308 during operation and to provide a substrate for mountingthe key assemblies 308 thereto. The key assembly support layer 400includes a plurality of apertures 402, the apertures 402 selectivelylocated to be disposed below the key assemblies 308. The apertures 402are sized and located to permit the energy director 404 to pass throughthe aperture 402 when a user depresses the key assembly 308 duringtyping such that the energy director 404 contacts a circuit board 406disposed below the key assembly support layer 400.

The circuit board 406 of the illustrated embodiment includes threelayers: a top contact layer 408, a spacer layer 410, and a bottomcontact layer 412. The top contact layer 408 may be a flexible layerhaving a plurality of contacts (not shown) printed on the bottom surfaceof the top contact layer 408. The bottom contact layer 412 may be arigid or flexible layer having a plurality of contacts (not shown)printed on the top surface of the bottom contact layer 412.

The spacer layer 410 is sandwiched between the top and bottom contactlayers 408 and 412, thereby separating the top contact layer 408 fromthe bottom contact layer 412 under normal conditions. The spacer layer410 includes a plurality of apertures 414. The apertures 414 areselectively sized and located as to be disposed below the energydirector 404 of the key assemblies 308.

As the energy director 404 is actuated downward, the top contact layer408 is deformed downward through one of the apertures 414 in the spacerlayer 410 such that a contact disposed on the bottom surface of the topcontact layer 408 is pressed into electrical communication with acontact disposed on a top surface of the bottom contact layer 412,thereby completing a circuit.

Completion of the circuit may result in a signal being sent to acomputer or other device attached to the keyboard, instructing thecomputer or device to take a specific action. The circuit board 406 ispreferably transparent or translucent to permit a substantial portion ofthe light hitting at least the bottom surface of the circuit board 406to pass through the circuit board 406.

Disposed below the circuit board 406 may be a backer layer 416. Thebacker layer 416 may be a rigid or semi-rigid layer and may be used toincrease the rigidity of the keyboard assembly 300. The backer layer 416may be transparent or translucent to permit a substantial portion of thelight hitting at least the bottom surface of the backer layer 416 topass through the backer layer 416.

A light guide assembly 418 may be disposed below the backer layer 416and may be used to back-light the cover 302. More specifically, thelight guide assembly 418 includes a light guide 420 and a light emissionassembly 422. Generally stated, the light emission assembly 422 directslight into the light guide 420, which redirects the light upward towardthe cover 302. The light guide 420 is preferably able to redirect thelight to the top surface of the cover 302 so as to illuminatesubstantially the entire top surface of the cover 302.

As a result of the transparent/translucent nature of the componentsdisposed above the light guide 420, the light guide assembly 418 ispreferably able to light substantially all of the top surface of thecover 302, although other percentages of illumination of the cover 302are within the spirit and scope of the presently claimed subject matter,such as percentages greater than about 10%, 20%, 30%, 40%, 50%, 60%,70%, 80%, or 90%.

Referring to FIG. 19, the light guide assembly 418 of FIG. 18 will bedescribed in further detail. The light guide assembly 418 includes oneor more light emitters 424 and the light guide 420. The light emitters424 may be any suitable light generating source, a few examples beingLEDs as illustrated, incandescent lights, etc. The light guide 420 maybe made of any transparent or translucent material able to transmitlight, a few suitable examples being acrylic and polycarbonatematerials.

The light guide 420 may include one or more light redirectors 426. Thelight redirectors 426 are positioned and shaped to redirect lightemitted from the light emitters 424 toward a top surface of the lightguide 420 so as to be directed toward a top surface of the keyboard. Inthe illustrated embodiment, the light emitters 424 emit light in ahorizontal direction. After the emitted light 428 hits the lightredirectors 426, the light redirectors 426 redirect the light fromanywhere between 0 to 180 degrees, and preferably 90 degrees, from theoriginal path of the emitted light, such that the emitted light isdirected toward the top surface of the keyboard.

In the illustrated embodiment, the light redirectors 426 are in the formof hemispherically-shaped recesses located in an array on the bottomsurface of the light guide 420. Although a specific shape of the lightredirectors 426 is illustrated and described, it should be appreciatedby those skilled in the art that alternately shaped light redirectorgeometries 426 are suitable for use with and are within the spirit andscope of the presently claimed subject matter.

The light guide 420 may also include a series of light reflectors 430disposed about the outer surface of the light guide 420. The lightreflectors 430 increase the efficiency of the light guide 420 byimpeding the emitted light 428 from passing out of the light guide 420except through a predetermined area, one suitable example being the topsurface of the light guide 420.

In the illustrated embodiment, the light reflectors 430 are formed fromreflective material attached to the sides (except the side in which thelight emitters 424 direct the emitted light toward to enter the lightguide) and the bottom surface of the light guide 420. The reflectivematerial includes a reflective surface which reflects any emitted lighthitting the reflective surface back into the light guide 420 forredirection toward the top surface of the light guide 420. A diffusingfilm may also be employed on the top surface.

Turning to FIG. 20, a user interface system 450 for permitting dataexchange with a user will be illustrated and described. The userinterface system 450 places the above described keyboard assembly 300and its associated subcomponents, such as the sensor assemblies 370 and372 and the warning assembly 456, in communication with another.Further, the user interface system 450 places the keyboard assembly 300and its associated subcomponents in communication with a computer 452.

The computer may be a well-known computer 452 adapted to send and/orreceive data from the keyboard assembly 300, and therefore will not bedescribed further herein for the sake of brevity. The controller 454 isadapted to send and/or receive signals from the keyboard assembly 300,its associated subcomponents, and/or a user, and control the operationof the keyboard assembly 300 and sensor assemblies 370 and 372 inaccordance with the information received. For instance, a user mayselect and enter a predetermined threshold sensor value, i.e., the levelat which the sensor assemblies will indicate detection of a cleaningfluid.

The user may select and enter a predetermined time value in which thefirst sensor assembly 370 detects a cleaning fluid, the second sensorassembly 372 must detect a cleaning fluid or a failed cleaning evolutionwill be indicated. The user may also select and enter predeterminedtimes or events in which cleaning will be required, such as upon boot upof a computer associated with the keyboard, upon a change in users, apredetermined duration after a logged successful cleaning, a certaintime of the day/week/month/year, etc.

The user may also select the manner in which data is sent to the user,i.e., via audio alarm, visual alarms and or messages, functional(locking out of keyboard), physical alarms (vibration), data reports,etc. The user may also select the parameters or format of the data sentto the user (a few suitable examples being the volume of audible alarms,the frequency and pattern of beeps, etc.), the characteristics of thevisual alarms (a few suitable examples being selecting an image to bedisplayed, frequency and pattern of flashes of light, etc.)

The user may also select and enter if a message (and what message)should be sent to the computer for display to the user related tocleaning of the keyboard. A few suitable examples would be indicatingthat cleaning is required, that cleaning has been completed, when thenext scheduled cleaning is to take place, instructions for cleaning,etc.

FIG. 21 illustrates one embodiment in which the user interface system450 has a graphical user interface 460 through which the user can enterdata to control the operation of the keyboard assembly 300. Theillustrated graphical user interface 460 is a software program that canbe installed on the computer, embedded in the keyboard hardware, orotherwise operably connected to the computer. Graphical user interfacesare well-known in the art and therefore will not be described furtherherein for the sake of brevity. It should be appreciated by thoseskilled in the art that a graphical user interface could be modified toallow a user to send and/or receive a wide variety of signals and dataas dictated by the user's needs.

The operation of the controller 454 in controlling the sensor assemblies370 and 372 will now be described. A predetermined threshold sensorvalue may be entered through the graphical user interface 460 via thekeyboard assembly 300 or any other suitable means. The controller 454then records the predetermined threshold sensor value.

After a signal is received from the sensor assembly 370 from one of thesensor groups indicating a potential sensing of a cleaning fluid, thecontroller 454 analyzes the signal received relative to thepredetermined threshold sensor value to determine if the signal receivedexceeds the predetermined threshold sensor value. If the value of thesignal received exceeds the predetermined threshold sensor value then a“cleaning fluid detected” or “sensor has been wiped” at the right sensorgroup is recorded.

If the value of the signal received does not reach the predeterminedthreshold sensor value, then a “failed cleaning fluid detection” isrecorded. This process is repeated for the left sensor group. After acleaning fluid detected signal is received by both the left and rightsensor groups by the controller, the controller 454 compares theduration of time between receipt of the cleaning fluid detected signals.If this value is less than a predetermined time cycle value entered bythe user, then a successful cleaning action is indicated by thecontroller via the warning assembly 456. If this value is more than thepredetermined time cycle valve entered by the user, then a failedcleaning action is acknowledged by the controller 454 and no change incleaning state or operation of the keyboard is initiated.

Although the controller 454 is depicted as a separate component from thekeyboard assembly 300 in the illustrated embodiment, it should be notedthat the controller 454 may be located in any suitable location. Forinstance, the controller 454 may be an integral component or group ofcomponents of the keyboard assembly 300, or may be a software programrunning on the computer.

Operation of the key board assembly 300 is further understood byreference to FIGS. 22A and 22B. A user will power on the keyboard,indicated by the start block 500. This initiates the warning triggersources described above and referred to by the block 502. The user mayoptionally turn on the back-lit key board feature, indicated by thedecision block 504. If the user activates the back-lit key feature, theintensity of the lighting level may be adjusted, indicated by the block506.

The keyboard is scanned to determine whether or not it is in the “cleanmode,” indicated by the decision block 508. If the keyboard is not inthe “clean mode,” the user may press the activation button 600 (FIG. 9)and indicated by the decision block 510. If the activation button 600 ispressed by the user, then the clean mode indicator light or status light602 is activated and indicated by the block 512. This also starts theclean mode time out timer, designated by the block 514.

As described above, the clean mode system is operational for only apredetermined period of time and decision block 516 assess whether ornot this time has expired. If the time has not expired, then thekeyboard remains in the clean mode until the user represses theactivation button 600, indicated by the block 518. If the user haspressed the activation button 600, then the clean mode indicator orstatus light 602 is turned off, indicated by the block 520.

The operational flow diagram continues to the decision block 522 todetermine whether any one of the triggering events has occurred. If thetriggering event has occurred, then the warning indicator, such as thewarning light 604, is activated, as set forth in the block 524. Also, anoptional data warning report may be trigger, indicated by the block 526.

Referring to FIG. 22B, if the trigger event has occurred and the warningfor cleaning is activated, the sensors are monitored to determinewhether or not they have been wiped, indicated by the decision block528. If the sensor has been wiped, then the sensor interval timer,indicated by the block 530 is initiated. As set forth in the decisionblock 532, the interval is monitored to determine whether the intervalperiod has expired. The timer may be set for any range of time, such asbetween one second up to three minutes or more, with a preferred rangebeing about 20 seconds. As noted above, this represents the period oftime in which (if the keyboard includes more than one sensor) allsensors must be wiped for a satisfactory cleaning.

If the timer has expired, then the sensor interval timer is reset, asindicated by the block 530. In the event that the sensor interval timerhas not expired, the sensor is monitored to determine whether or not itmeets the threshold condition (i.e., has been wiped), indicated by theblock 534. If the second sensor has not been wiped, the sensor intervaltimer is reevaluated to determine whether or not the interval timer hasexpired.

It should be noted that this portion of the flow diagram is repeated forthe number of sensors embedded in the keyboard. As a non-limitingexample, if the keyboard assembly includes five sensors, then eachsensor must be evaluated within the allotted time to determine whetherall sensors have been wiped clean.

Still referring to FIG. 22B, if the sensor, indicated in block 534,meets the threshold, then the warning indicator is turned off, indicatedby the block 536. The warning triggers are reset, indicated by the block538, and finally a cleaning date report may be generated, indicated bythe block 540.

While illustrative embodiments have been illustrated and described, itwill be appreciated that various changes can be made therein withoutdeparting from the spirit and scope of the presently claimed subjectmatter.

The embodiments of the present subject matter in which an exclusiveproperty or privilege is claimed are defined as follows:

1. A combination keyboard and cover assembly, comprising: (a) a keyboardhaving at least one input key assembly positioned within a housing; and(b) a cover sized and configured to substantially encase the keyboard,the cover having a substantially flat top surface to resist wrinklingduring use and a predetermined flexibility to substantially mechanicallyisolate one input key assembly from a second input key assembly during akey stroke input travel distance of at least 0.05 inches.
 2. Thecombination keyboard and cover assembly of claim 1, wherein the cover isformed from an elastomeric material.
 3. The combination keyboard andcover assembly of claim 1, wherein the cover is removably coupled to thekeyboard.
 4. The combination keyboard and cover assembly of claim 1,wherein the cover is formed from a translucent material to permit the atleast one input key assembly to be visible through the cover withsubstantial clarity.
 5. The combination keyboard and cover assembly ofclaim 1, wherein the cover further comprises a protective coating. 6.The combination keyboard and cover assembly of claim 1, wherein thecover is coupled to the keyboard by wrapping around sides of thekeyboard.
 7. The combination keyboard and cover assembly of claim 1,wherein the keyboard is backlit by a lighting assembly disposed withinthe keyboard.